Archive for the 'Biochemistry' Category

In the spirit of conservation, recycling, and urine fetishes comes Repronex, a drug that comes from the concentrated urine of post-menopausal women. It’s used to stimulate the release of FSH and LH, two pituitary hormones important for sex hormone release and maintenance of most things sexual in the body.

Apparently it’s been around for quite some time, but, like my used car, it’s new to me.

Also in the “abusing nature for all it’s worth category”: Miacalcin, a salmon version of our body’s natural hormone, calcitonin. (The salmon version is much more potent than the human version. Go figger.)

(Okay, okay, it’s a bit of a dramatic extreme, but it’s true. I swear.)

Black licorice contains a compound called glycyrrhizic acid, which mimics a hormone in your body (aldosterone), which causes you to lose potassium through your urine. This causes what’s called hypokalemia, which can lead to abnormal heart rhythms. (Maintaining the right level of potassium in your body is vitally important. Too much or too little can cause abnormal heart rhythms. Luckily your kidneys usually keep everything juuuuust right.)

A new wave of ingestible chemicals are on their way, and while I’m still skeptical, the active ingredient is a common molecule called AMP, found naturally in the human body as an enzyme regulator (as well as other uses of which I’m unaware).

The street name for chemicals is “bitter blockers,” because when ingested with bitter foods, bitter-detecting taste buds are less activated, making us taste less of the bitter in the foods and drinks. The New York Times has a piece on this latest biotechnology, and food and beverage companies seem to be swarming.

According to the Times:

bq(quote). While many people think sugar and salt are added to foods simply to increase flavor, often the additives mask other, less agreeable tastes. Processed foods, like canned soups, sauces and potato chips, have high amounts of salt to mask the bitter tastes that emerge during the extremely hot cooking process. Some soft drinks are filled with sugars to tone down the bitter taste of caffeine.

The product has been received well in the lab, at least, to de-bitter grapefruit juice and coffee; in an even more useful setting, the bitter blockers might be used to make drugs more tolerable to swallow, including HIV cocktails, which are infamous for their intolerable taste.

If the AMP works without side effects, I think these could be a blessing to nutritionists–allowing manufacturers to add less salt, sugar, and fat to products in order to mask unwanted flavors. Until more Americans learn to slow down or eat healthier, hopefully microwave dinners will be a little better for us. But I still tend to agree with Michael F. Jacobson, executive director of the Center for Science in the Public Interest in Washington:

bq(quote). “If companies use this to market products that are healthier, more power to them. If they used higher-quality ingredients or didn’t cook them to death, they wouldn’t taste bitter in the first place.”

Props to the placenta. If you remember your Health 101 course from high school, the placenta allows woman and fetus to share nutrients, immune cells, and even oxygen without sharing the same blood. (It also can make almost every hormone the rest of the body’s organs can make, but that’s for another day.) Oxygen floats around your blood inside a molecule called hemoglobin (one part of the hemoglobin molecule complex contains iron, which is what makes your blood red). But how does the oxygen get transfered from one blood system to the other? Simple. As the woman’s hemoglobin starts to dump off her oxygen, the fetus’s hemoglobin scoops it up.

Take a look at the graph to the right. (Don’t run away! Please!) On the Y-axis, you’ve got hemoglobin O2 saturation (ie: the percentage of hemoglobins that are still carrying oxygen, and haven’t released it yet). On the X-axis, you’ve got the pressure of oxygen in your blood (ie: how much oxygen’s in your blood at a certain spot in your body – it decreases the further you get from the heart). Now take a look at the blue line–that’s the adult line. At 40% pressure, about half of the hemoglobins still have their oxygen. But as you get further from the heart, hemoglobins start dumping their oxygens more rapidly.

Now look at the fetal, red line. It’s above the blue one. So, at the same pressure, more of the fetal hemoglobin still has its oxygen. Sum it all up: when the adult is starting to dump off its oxygen, the fetus is still holding tighter to its oxygen, so it collects any oxygen that the woman’s hemoglobin is releasing.

Here’s the trick–fetal hemoglobin is just slightly different from adult hemoglobin. At birth, the baby stops producing its fetal hemoglobin, and starts producing adult hemoglobin, since it’s ready to start breathing on its own.